Abstract
Economic development of deep tight gas reservoirs is a challenge our industry has struggled with for many years. This paper describes how a very deep (15688', 4783 m TVD) well with a horizontal section (over 86°) of over 630 m (2,066') was completed for stimulation with multiple fractures. Multiple packers and sliding side doors provided isolation for 4 separate fracs and a 5th zone containing 52m (171') of perforated interval in the 7" casing. Extreme overbalance perforating techniques using tubing conveyed perforating guns and high pressure nitrogen were used to perforate and break down each of the 0.6m (2') of perforated intervals for the 4 fracs and 853 perforations in the 5th unstimulated zone. To achieve a high shot density, a special perforating tubing anchor was designed to allow two different perforating guns to perforate exactly the same interval in one trip. An open annulus treating system was used with a 4½ frac string for observation of the bottomhole treating pressure during fracture operations. A total of over 2 million pounds of high strength proppar.t was pumped into the 4 fracs at rates in excess of 5.6m’/min (35 BPM). High bottomhole temperatures (290°F, 143°C), reservoir pressures (9000 psi, 620 bar), and bottomhole treating pressures (16000 psi, 1100 bar) added to the complexity of design and operation of equipment. Over 5,700m (18,70001 of ¾" coiled tubing was run to TD and used in conjunction with a downhole force generator to open and close the sliding side doors.
